This invention is directed generally to the field of miniature motorized racing vehicles, and, in particular, to devices for protecting the drive trains of such vehicles.
The racing of miniature, motorized, usually radio-controlled vehicles (commonly termed "RC" vehicles) has become a very popular hobby. For some, in fact, the racing of RC vehicles has become a serious international sport.
Like their full-sized cousins, a typical RC racing vehicle has a drive train which includes a transmission. The care and upkeep of vital drive train components has been found to be as necessary in RC vehicles as it is in full-sized vehicles.
In this regard, it has been found to be necessary to protect the drive train components in an RC racing vehicle from the sudden over-torquing caused when the vehicle bounces into the air at high speeds and then lands back on the track again. When the vehicle leaves the ground, the sudden lack of load on the drive wheels causes the motor to accelerate to very high rpms. When the vehicle comes to earth again, the sudden reintroduction of the load on the drive wheels can do serious damage to the drive train.
Prior art methods of protecting RC vehicle drive trains have generally employed one or more clutch assemblies. When the drive train is suddenly over-torqued, a clutch plate is allowed to slip within the assembly, thereby protecting the drive train components.
There is a problem, however, with the use of such clutch assemblies. To adequately protect the more fragile drive train components, the slippage threshold on the clutch plate must often be set so low that the clutch assembly tends to slip during normal operations. The problem is most commonly experienced during accelerations and operations at high speeds, and can become acute after the clutch plate becomes hot. Such slippage can severely impair the performance of the racing vehicle.
Accordingly, there is a need for a practical, inexpensive device which is capable of protecting the drive train of a miniature, motorized racing vehicle, but which has a minimum tendency to slip under normal racing conditions.